In conventional analog PET scanning, photomultipliers that are used to detect light output from the scintillator are limited in counting capabilities due to size and processing capabilities. To count photon events, light emitted from the scintillator is dispersed to multiple photomultiplier detectors. This sharing of information limits the capability of the PET detector to accurately process count rate information and location of the origin of the photon.
The Philips difference is digital. Unlike analog PET/CT scanners that use photomultipliers to detect light, the Vereos PET/CT scanner uses proprietary Digital Photon Counting (DPC) technology. It detects photons emitted from radiotracers individually by converting the scintillating light that collects them directly into a digital signal. This 1:1 coupling of crystals to light sensors provides faster time-of-flight than analog,* and approximately twice the sensitivity gain, volumetric resolution and quantitative accuracy.